The following is an approximate copy of a letter I sent to the Institute of Medicine, regarding their forthcoming vitamin D recommendations.
Thank you for the opportunity to express my opinions regarding the forthcoming determination by the Institute of Medicine as to whether the current recommended daily allowance of vitamin D should be revised to a higher level. In my opinion, the decision will be one of the most important in the annals of medicine, as it could positively or negatively affect the health of millions in the US. We have, as a society, ceased to spend as much time in the sunlight as we once did. This is due to our habits of working indoors and scrupulously avoiding sunlight when we venture outdoors. In consequence, we have become critically deficient in vitamin D, a potent steroid hormone whose chemical receptors are found throughout the body. Vitamin D levels are declining in the US population, and that does not bode well for the health US citizens. It has been estimated that maintaining serum levels 25(OH)D of 55 ng/ml could prevent 85,000 cases of breast cancer and 60,000 cases of colon cancer. If there were no other source of vitamin D, achieving that serum level would require the ingestion of about 5,500 IU of vitamin D3 daily for men and slightly less for women. It is obvious that the current recommendations of 400 IU are woefully inadequate.
In addition, sudden death from heart attack is about 2.4 times higher in men with the lowest levels of vitamin D compared to those with the highest levels. It would be possible to go through a long list of diseases that correlate closely to vitamin D deficiency, such as MS, osteoporosis, twenty major cancers, hypertension, arthritis, Lupus, etc., but that would be laborious for both of us. My book, Vitamin D3 and Solar Power, has 800 references to the medical/scientific literature and discusses the influence of vitamin D on more than 100 diseases and conditions.
One double-blind, placebo controlled, interventional study has already determined that four years of vitamin D and calcium supplementation correlated to a 60-77% reduced risk of all cancers in women. The researchers have just received a $4,000,000 grant to continue that research with higher dosages of vitamin D. Science often demands that such studies be conducted before any changes in recommendations are made. However, this may cause delays in action that could cost millions of lives. No such study could ever be attempted among smokers. Such a study would require that half of a group of non-smokers was given cigarettes, taught to smoke and then compared with the other half for death rates. Such a study was never done to furnish conclusive proof that smoking increased the risk of lung cancer. The reasons: (1) it would not have been ethical, and (2) the evidence from observation made the conclusion obvious and compelling. In my opinion, the evidence for higher vitamin D recommendations, either as supplementation or as sunlight exposure, is just as compelling. The researchers in the aforementioned cancer study for instance, stated that the reduction in cancer produced by vitamin D supplementation was about twice that which would be expected if all women stopped smoking.
We cannot afford to wait for more studies to find conclusive proof of the need for higher supplemental recommendations while millions more people die. There is not one whit of evidence that vitamin D supplementation of 10,000 IU per day for an adult is toxic.
I also suggest that you recommend regular, non-burning sunlight exposure as the most natural way to achieve optimal levels of vitamin D.
Marc Sorenson, EdD
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Garland, C et al. What is the dose-response relationship between vitamin D and cancer risk? Nutrition Reviews 2007;65:S91-5.
Giovannucci, E. et al. 25-hydroxy-vitamin D and risk of myocardial infarction in men. Ann Intern Med 2008;168:1174-80.
Lappe, J. et al. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Am J Clin Nutr 2007;85:1586–91.
Vieth, R. Vitamin D supplementation, 25-hydroxyvitamin D concentrations and safety. Am J Clin Nutr 1999;69:842-56.